<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <div id="app" style="color: red;font-size: 20px;">
      hello{{msg}}
      <h></h>
    </div>
    <script src="dist/vue.js"></script>
    <script>
      const vm = new Vue({
        el: "#app",
        data() {
          return {
            msg: "vue2",
            a: {
              b: 20,
            },
            arr: [1, 2, 3],
            objArr: [
              {
                a: 1,
              },
            ],
          };
        },
        props: {},
        watch: {},
      });
      console.log(vm);
      vm._data.arr.push(4);
      vm._data.objArr.push({
        name: '1'
      });
    </script>
  </body>
</html>
